Multi roll and alignment system for deep rolling

ABSTRACT

The present invention provides an alignment system for deep rolling tools wherein at least one of an upper or lower tool includes an appendage received in the opposite tool when the upper and lower tools are positioned about a work piece. The present invention further provides a multi roll system for deep rolling wherein both of an upper and a lower tool are provided, each of the upper and lower tools having at least two radially offset work rolls supported on substantially coplanar back up rollers. Upon engagement with a work piece, work rolls are engaged therewith in at least four radial points of contact.

[0001] This application claims the benefit of the filing date of U.S.Provisional Application Serial No. 60/411,602, filed Sep. 18, 2002, andhereby incorporated by reference in its entirety

TECHNICAL FIELD

[0002] The present invention relates generally to tools for deeprolling, and more particularly to an apparatus having upper and lowertools with a connecting mechanism to align and stabilize the upper andlower tools relative to one another during a deep rolling process.

BACKGROUND OF THE INVENTION

[0003] Deep rolling apparatuses and deep rolling systems having beenknown for many years. The prior art deep rolling systems generally useda lower tool in conjunction with an upper tool to deep roll a crankshaftto increase the strength around lobes of a crankshaft for use invehicles and other applications. A variety of upper tools and lowertools have been used in the prior art. The need for deep rolling isbecoming ever more important because automotive vehicles and componentsthereof are being down sized to reduce weight and improve fuelefficiency, hence smaller engines and crankshafts are needed. With thesesmaller engines and crankshafts there is a need to improve the fatiguestrength and durability of the smaller down sized crankshafts. Thisimproved fatigue strength and durability is accomplished by deep rollingof the fillets or lobes and other circular joint areas on thecrankshaft. The strength and durability of crank pins of the mainbearing journals can be significantly increased by deep rollingcompressive stresses into the middle of the annular fillets between thepin journals and the adjacent counter weights or balancing webs.

[0004] Some of the prior art lower tools use a system of rollers tosupport and roll the crankshaft while the upper tool uses work rolls toactually do the strengthening and finishing of the work pieces such ascamshafts and crankshafts. Other types of lower work roll tools includea housing and side plate which hold and locate back up rollers andshafts. The back up rollers will operate to rotate a work roll which isheld in place by a cage retainer and cage. The work roll will roll alongthe lobes and other fillets of a crankshaft to deep roll compressivestresses into such areas. The lower work rolls will work in unison withwork rolls on an upper tool. Generally, the prior art deep rolling tollsincluded a single point work roll in an upper tool and two three pointwork rolls in the lower unit.

[0005] In the prior art the upper and lower tools were separate anddistinct from each other and were capable of travel or “walking”relative to each other in an axial direction along the crankshaft beingdeep rolled. Furthermore, the fewer work rolls working the unit thelonger it takes to deep roll the compressive stresses into thecrankshaft, thus increasing the cost and time of the deep rollingprocess.

[0006] Therefore, there is a need in the art for a low cost integratedconnecting mechanism to align and stabilize a lower tool with respect toan upper tool during the deep rolling process.

[0007] Furthermore, there is a need in the art for a four-point workroll mechanism to increase the speed and precision of the compressivestresses deep rolled into a crankshaft.

[0008] One object of the present invention is to provide a novel designfor an alignment mechanism between an upper and lower tool for a deeprolling apparatus.

[0009] Another object of the present invention is to provide a design ofa novel four-point work roll mechanism for a deep rolling apparatus.

[0010] Still another object of the present invention is to provide adesign of a deep rolling tool that includes two sets of work rolls on anupper tool and two sets of work rolls on a lower tool to increase thespeed and efficiency of the deep rolling process.

[0011] Other objects, features and advantages of the present inventionwill become apparent from the subsequent description, taken inconjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0012]FIG. 1 shows a side view of an upper and lower tool connectingmechanism according to the present invention;

[0013]FIG. 2 shows a side view of an alternate embodiment of aconnecting mechanism to connect an upper tool and lower tool of a deeprolling apparatus;

[0014]FIG. 3 shows a side view of a four-point work roll set up for usein a deep rolling apparatus.

SUMMARY OF THE PRESENT INVENTION

[0015] According to the present invention, the foregoing and otherobjects and advantages are attained by novel designs for an upper andlower work tool for a deep rolling tool apparatus. The upper tool wouldinclude an appendage extending from an end thereof. The lower tool wouldinclude a slot or channel in an end thereof adjacent to the upper tool.The appendage and slot would mate with one another to secure the uppertool to the lower tool with respect to a common shared plane. The deeprolling tool apparatus also could include a novel four-point work rollsetup. The upper tool would include a plurality of work rolls while thelower tool will also include a plurality of work rolls. In oneembodiment four work rolls would be included with both the upper andlower tool thus giving the four-point work roll deep rolling apparatus.

DESCRIPTION OF THE PREFERRED EMBODIMENT AND BEST MODE OF CARRYING OUTTHE INVENTION

[0016]FIG. 1 and FIG. 2 show one of many designs known for a lower worktool and an upper work tool for use in a deep rolling machine accordingto the present invention. It should be noted this invention can be usedwith any of the known lower tool designs and upper tool designs and anyknown deep rolling process apparatuses. The lower work tool 10 includesa main body 12 generally forming a rectangular shape with a cutout 14 onone side thereof. It should also be noted that a generally L-shaped mainbody might also be used in a separate embodiment contemplated for alower work tool, or any other general shape that is capable of holdingand rolling a cam shaft, crankshaft or the like. The main body 12includes a housing and a side plate connected to one another, via anyknown fasteners, each having ports 16 therein to allow for lubricationduring operation and easier cleaning of the lower tool mechanism 10during operation thereof. It should be noted that any other number orset of slots, or even none may be used depending on the lubricationrequirements and the design environment of the deep rolling tools. Afirst and second shaft 18, 20 are supported between the housing and sideplate. A first and second backup roller are rotatably supported aroundthe first and second shaft 18, 20 respectively. A bearing 26 is locatedbetween the backup roller 22, 24 and an inner race 28 for each backuproll. The inner race 28 will contact the shaft 18, 20 during rotation ofthe backup rolls. A first and second cage retainer 30, 32 are connectedto an outer surface of the V-shaped cutout in the lower tool main body10. A dual cage retainer 34 is located at the bottom portion of theV-shaped or other shaped notch in the lower tool 10 and is used to alignthe cage 36 in a necessary position.

[0017] A first and second work roll 38, 40 are located at four separatelocations and held in place in the lower tool by the cages 36. The workrolls 38, 40 will contact the backup roller 22, 24 on one side thereofand on an opposite side thereof will contact the work piece 42 beingrolled. Therefore, the backup rolls 22, 24 in the lower tool will rotateat the speed with which the crankshaft or work piece 42 is beingrotated.

[0018] The upper tool 44 will include a body member 46 that includes ahousing and side plate, or in another embodiment or two-piece housingtool, each having porting 48 such as that described above forlubricating and cleaning of the upper tool 44. The upper tool 44 willinclude a shaft 50 and a backup roll 52 arranged around the shaft. Itshould be noted that it is contemplated to have a plurality of backuprolls and shafts within an upper tool mechanism also. The upper tool 44will include a cage retainer 54 and a cage 56 on one end thereof,wherein the cage 56 will hold up to two work rolls 58 which will contactthe work piece being rolled and the backup roll 52 on an outer surfacethereof. The backup roll 52 includes an inner race 60 and a bearing 62,as described in the lower tool.

[0019] The upper tool 44 will include an appendage or male member 64extending from a side adjacent to the edge or side having the work roll58 thereon. The male member or appendage 64, as shown in FIG. 1, canhave a generally L-shape. The appendage 54 will be made of a similarmaterial or different material to that of the upper tool 44 and willeither be mechanically, chemically, magnetically or electronicallyconnected to either the side plate or the housing or one end of eitheror both parts of the upper tool 44. One embodiment contemplates weldingthe appendage 64 thereon, another embodiment contemplates securing themale member 64 thereon via a fastener, another embodiment contemplatesmolding, forming, casting, brazing, gluing, epoxying, or any other knownchemical bonding method.

[0020] It should be noted that the shape of the appendage 64 may also bevaried from the generally L-shaped configuration shown in FIG. 1. Theappendage also has a predetermined width and will extend a predetermineddistance from the side of the upper tool 44 such that it will mate withand inter-engage with a like receptacle 66 in the lower tool. Therefore,any shape appendage 64 may be used depending on the environmentalengineering and manufacturing requirements of the deep roll mechanism inthe manufacturing environment. It is also contemplated to have theappendage made of a different material such as a hard ceramic, plastic,or any metal known.

[0021] The lower tool 10 will include a slot or channel 66 that will beused to receive and hold the appendage or male member 64 in a similarplane with respect to the lower tool 10. This will ensure that the upperand lower tool 10, 44 do not exhibit any axial movement relative to eachother along the work piece 42 being worked. The receptacle or femalemember 66 will be connected to or arranged on an upper surface of eitherthe side plate or housing of the lower tool 10 directly adjacent to theside of the upper tool 44 having the appendage 64. The female member 66will be made of the same or a like material or any other material asnoted above and connected by any known means including mechanical,chemical, any fastener, welding, casting, molding, forming, or othertype of connecting means known. The slot 66 will be such that the widthof the slot will mimic the width of the appendage 64 thus allowing foreasy insertion and removal of the appendage 64 into the slot 66 whilestill allowing for radial movement between the upper tool 44 and lowertool 10. The appendage 64 and slot 66 may also include a lockingmechanism therebetween. The male and female connections will restrict oreliminate any axial movement between the tools, thus keeping them fromwalking along the work piece 42 being rolled, thus increasing theefficiency and proper alignment of the stresses being rolled into theshafts. The use of the male and female member will allow the upper andlower tool to remain on a similar parallel plane while also allowing forany necessary radial movement between the tools.

[0022]FIG. 2 shows an alternate embodiment of the mechanism to keep theupper 44 and lower tool 10 on the same parallel plane. In thisembodiment an appendage 64 extends from both sides of the upper tool 44.Each appendage 64 would have an orifice 70 therein where a fastener 72would be inserted. The lower tool 10 would include an orifice 74 on atop end thereof that mimics the shape of the end of the fastener 72 usedin the upper tool 44. The orifice 74 would be molded, cast, formed,etc., directly within the lower tool 10 prior to manufacture of thelower tool or may be added as a secondary process via drilling or otherboring techniques. In operation the upper tool 44 would have theappendage 64 on either or both sides and a fastener 72 would be placedeither directly into the appendage 64 or an orifice would be placed inthe appendage 64 and the fastener 72 would be placed therein. Thefastener would then have its free end placed into the orifice or femaleslot 74 of the lower tool 10 thus allowing for the upper and lower toolto remain on a parallel plane while allowing for radial movement betweenthe upper and lower tool for any necessary variances in the radius ofthe work piece 42 being rolled. It should be noted that FIG. 2 shows thefastener 72 only on one side but it is contemplated to have a fastener72 or pin on both sides of the upper and lower tool such that the planewill be similarly maintained through the entire work rolling process. Itshould be noted that any type of fastener, pin, shovel, rod, etc may beused to connect the upper tool 44 to the lower tool 44 to ensure thesame plane in the axial direction. Alternative embodiments arecontemplated (not shown) wherein the appendage is attached to the lowertool, and is received in a slot or channel in the upper tool. Furtherembodiments (not shown) are also contemplated wherein each of the upperand lower tools includes an appendage.

[0023]FIG. 3 shows a novel four-point work rolling mechanism 100 for adeep rolling process. The four-point mechanism 100 would include anupper tool 102 and lower tool 104 which are generally set up as thosedescribed above and further detail will not therefore be given. Thelower tool 104 and upper tool 102 will each include a body 106, 108having a first 110, 112 and second backup roll 114, 116 in both theupper 102 and lower tool 104 respectively. The upper 106 and lower body108 will also include a notch 118, 120 on one side of the body thereof.Within this notch 118, 120 will be located a first 122, 124 and secondcage 126, 128. The first 122, 124 and second cage 126, 128 will hold thefirst 130, 132 and second work roller 134, 136 for each individual cagefor each upper 102 and lower tool 104. Therefore up to eight work rollscan be used to roll the work piece 138 in the deep rolling process. Fourwork rolls will be located in the upper tool 102 and four work rollswill be locate in the lower tool 104. Each of the work rolls 130, 132,134, 136 will contact the backup roll on one side thereof and on theopposite side thereof the work piece 138 being rolled. It is alsocontemplated to just having four work rolls, i.e. one in each cage, butalways having the four-point work rolling system for the upper and lowertool in the deep rolling process. It should be noted that it is alsocontemplated to include up to six or eight point work rolling mechanismsin the contemplated invention by increasing the number of work rollscontacting the known backup rolls or even adding further backup rollsinto the upper and lower tools without affecting the weight, cost orsize of the deep rolling mechanisms. It should be noted that it iscontemplated to make the four-point work rolling system out of any ofthe known materials for current work rolling mechanisms such asaluminum, metal or any other type of hardened composites, plastics ormetal material.

[0024] While it may be apparent that the preferred embodiments of theinvention disclosed are well calculated to fill benefits, objects oradvantages of the invention, it will be appreciated that the embodimentsdisclosed herein are susceptible of modification, and the presentdescription should not be understood to limit the scope of the inventionin any manner. Thus, those skilled in the art will appreciated thatvarious alterations might be made to the presently disclosed embodimentswithout departing from the spirit and scope of the present invention.

What is claimed is:
 1. An apparatus for deep rolling a work piececomprising: an upper tool having a housing with at least one work rolland a backup roller positioned therein, said upper tool having anappendage; a lower tool having a housing with a channel that receivessaid appendage when said upper and lower tools are positioned about awork piece; wherein an engagement of said appendage with said lower toolminimizes relative axial displacement between said upper and lower toolsduring deep rolling.
 2. The apparatus of claim 1 wherein said appendageis generally L-shaped, and extends substantially laterally from an endof said upper tool.
 3. The apparatus of claim 1 wherein said appendageis substantially cylindrical.
 4. The apparatus of claim 1 wherein theposition of said appendage relative to said upper tool is adjustable. 5.The apparatus of claim 1 wherein said appendage is metallic.
 6. Theapparatus of claim 1 wherein said appendage is non-metallic.
 7. Theapparatus of claim 1 wherein said appendage comprises an elongate memberthreadedly engaged with said upper tool.
 8. The apparatus of claim 5wherein said appendage is welded or formed to the upper tool.
 9. Theapparatus of claim 5 wherein said appendage is attached to the uppertool with a fastener.
 10. The apparatus of claim 1 wherein saidappendage is attached to said upper tool by chemical bonding means. 11.An apparatus for deep rolling a work piece comprising: a first toolhaving at least one work roll and a back-up roller; a second tool havingat least one work roll and a back-up roller; wherein at least one ofsaid first and second tools is movable to engage said first and saidsecond tools about substantially opposite sides of a work piece; and atleast one of said first and second tools includes an appendage extendinggenerally toward the opposite tool, said appendage received therein whensaid first and second tools are engaged with a work piece, therebymaintaining said first and second tools in a substantially coplanarrelationship during deep rolling.
 12. The apparatus of claim 11 whereinsaid first tool comprises two work rolls, and said second tool comprisesfour work rolls.
 13. The apparatus of claim 12 wherein said first toolcomprises four work rolls and said second tool comprises four workrolls.
 14. The apparatus of claim 11 wherein said first tool comprises aplurality of appendages.
 15. The apparatus of claim 11 wherein saidfirst and second tools each comprise at least one appendage.
 16. A deeprolling apparatus comprising: an upper tool having at least two radiallyoffset work rolls contacting substantially coplanar back up rollers; alower tool having at least two radially offset work rolls contactingsubstantially coplanar back up rollers; at least one of said tools beingmovable relative to the other said tool to engage a work piece therebetween, wherein said upper and lower tools are adapted to engage a workpiece in at least four radial points of contact.
 17. An apparatusaccording to claim 16 wherein: said upper tool comprises two work rollssupported on each of two back up rollers; said lower tool comprises twowork rolls supported on each of two back up rollers.
 18. An apparatusaccording to claim 16 wherein at least one of said first and secondtools includes an appendage extending generally toward the oppositetool, said appendage received therein when said first and second toolsare engaged with a work piece, thereby maintaining said upper and lowertools in a substantially coplanar fashion during deep rolling.
 19. Adeep rolling apparatus, said apparatus including: an upper tool havingat least one work roll contacting a back up roller; a lower tool havingat least one work roll contacting each of two back up rollers; whereinsaid upper and lower tools are adapted to engage a work piece in atleast three radial points of contact.
 20. The apparatus of claim 19wherein: said upper tool comprises two work rolls supported on said backup roller; said lower tool comprises two work rolls supported on each oftwo back up rollers; wherein said upper and lower tools are adapted toengage a work piece in at least six radial points of contact.